/*
 * Copyright (C) 2012 Roman Yakovenko <b179a9@gmail.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is furnished to do
 * so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package com.b17.crypto.core;

public class Utils {

    public static void swap(byte[] array, int i, int j) {
        byte tmp = array[i];
        array[i] = array[j];
        array[j] = tmp;
    }

    public static int rol(int value, int positions) {
        return (value << positions) | (value >> (Integer.SIZE - positions));
    }

    public static int toInteger(byte[] bytes) {
        assert (bytes.length <= 4);
        int result = 0;
        for (int i = 0; i < bytes.length; i++) {
            result = result << 8;
            result ^= bytes[i] & 0xFF;
        }
        return result;
    }

    public static byte[] toBytes(int value) {
        byte[] result = new byte[4];
        for (int i = 0; i < result.length; i++) {
            result[i] = (byte) (value >> (8 * (7 - i)));
        }
        return result;
    }
}
